Home base stations, home NodeBs, femto eNodeBs or any other type of home access device (in the following referred to as “HeNB”) have become a widely discussed topic within 3rd Generation Partnership Project (3GPP) as well as in the operator and manufacturer community. When deployed in homes and offices, HeNBs allow subscribers to use their existing handsets—in a building—with significantly improved coverage and increased broadband wireless performance. Moreover, Internet Protocol (IP) based architecture allows deployment and management in virtually any environment with broadband Internet service.
With the introduction of High Speed Downlink Packet Access (HSDPA) in various commercial networks, operators noticed quite substantial date rate, i.e. capacity, consumption of single users. Those are in most cases users staying at home and using a HSDPA data card or the like for substantial Internet surfing like downloading movies etc. However, existing mobile communication systems (e.g. Global System for Mobile communications (GSM), Wideband Code Division Multiple Access (WCDMA/HSDPA) are not optimal suited for such home-based application, as those were developed and defined under the assumption of coordinated network deployment, whereas HeNBs are typically associated with uncoordinated and large scale deployment.
In HeNB scenarios, it is generally assumed that an end user is buying a cheap (Wireless Local Area Network (WLAN) like) product and also installs this physical entity at his home. Such a HeNB would then provide coverage/service to the terminals registered by the owner of the HeNB. Still the HeNB would use the same spectrum owned by the operator and as such at least partly the spectrum the operator is using to provide macro cell coverage to the area where the HeNB is located in.
Moreover, sharing and pooling properties of the core network, where several operator's core networks are attached to the same access node or foreign mobile terminal devices or user equipments (UEs) roam into a HeNB nominally “owned” by a certain operator, should be hidden to the HeNB, in order to ease handling of the HeNB. In general, conventional access devices, such as NodeBs or eNodeBs, being function-wise similar to HeNBs, bear a lot of nodal functions which are not necessary for simple home operation.
It has recently emerged that operators are interested in a so called local break-out (LBO) of “bulk” traffic. LBO is to be understood as a delivery of Internet traffic (or other bulk traffic) in a way that it does not transit across the operator's EPC, i.e. the Internet traffic would be forwarded to and received from the Internet via a gateway local to the base station without having to transit through the operator's core network nodes. LBO could also apply to voice traffic between two user equipments (UEs) in the same local area service area, where a local area service is a region in which local services adopting LBO can be deployed.
The deployment of HeNBs in LTE will have a strong impact on scalability at the EPC due to the very large deployment scale and therefore high numbers of interfaces to be established between HeNBs and EPC. Also, such deployment will cause an increase in the cost of operation and maintenance (O&M) operations as the O&M network will have to provide monitoring and control of all HeNBs.
However, current LTE standard specifications allow traffic breakout towards the public IP network only via a so called Public Domain Network Gateway (PDN GW). This configuration does not allow to offload traffic relative to Internet services from the centralized EPC, putting constraints on the EPC capacity and causing an increase of cost per bit of information traveling across the EPC.